Rascal Does Not Dream of Bunny Girl Senpai (manga)

"Forget what you saw today."There's something odd about Sakuta Azusagawa, an acerbic, standoffish high schooler who doesn't even own a cell phone in this day and age. And perhaps strange things happen to strange people, which is why on the last day of the Golden Week holiday, in a tranquil library, he meets a wild bunny girl. With that unforgettable encounter, their bizarre and mysterious love story begins.

Part of the Rascal Does Not Dream manga series by Hajime Kamoshida.